Information Dynamics In Open Quantum Systems

California Institute Of Technology, Pasadena CA

Investigators

Abstract

Recent theoretical work in quantum optics has revealed deep connections between measurement and decoherence, which may be understood as dynamical counterparts of the connection between information and entropy. This progress has largely been enabled by quantum trajectory theory, which we seek to verify experimentally. To do so we will first implement and test quantitatively two advanced methods for real-time quantum measurement (adaptive homodyne detection and quantum Kalman filtering), which have been derived on the basis of quantum trajectory theory. We will then utilize these techniques in experiments on hypersensitivity to perturbations, quantifying the amount of information that must continuously be gathered about environmental perturbations to keep the entropy of a system below a fixed value. Quantum trajectory theory provides a basis for predicting how this quantity should vary with the complexity of the observed system's dynamics.